1 /*
2 * Copyright (c) 2017, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_GC_G1_G1FULLGCPREPARETASK_HPP
26 #define SHARE_GC_G1_G1FULLGCPREPARETASK_HPP
27
28 #include "gc/g1/g1FullGCTask.hpp"
29 #include "gc/g1/heapRegion.hpp"
30 #include "memory/allocation.hpp"
31
32 class G1CollectedHeap;
33 class G1CMBitMap;
34 class G1FullCollector;
35 class G1FullGCCompactionPoint;
36 class HeapRegion;
37
38 // Determines the regions in the heap that should be part of the compaction and
39 // distributes them among the compaction queues in round-robin fashion.
40 class G1DetermineCompactionQueueClosure : public HeapRegionClosure {
41 G1CollectedHeap* _g1h;
42 G1FullCollector* _collector;
43 uint _cur_worker;
44
45 inline void free_empty_humongous_region(HeapRegion* hr);
46
47 inline bool should_compact(HeapRegion* hr) const;
48
49 // Returns the current worker id to assign a compaction point to, and selects
50 // the next one round-robin style.
51 inline uint next_worker();
52
53 inline G1FullGCCompactionPoint* next_compaction_point();
54
55 inline void add_to_compaction_queue(HeapRegion* hr);
56
57 public:
58 G1DetermineCompactionQueueClosure(G1FullCollector* collector);
59
60 inline bool do_heap_region(HeapRegion* hr) override;
61 };
62
63 class G1FullGCPrepareTask : public G1FullGCTask {
64 volatile bool _has_free_compaction_targets;
65 HeapRegionClaimer _hrclaimer;
66
67 void set_has_free_compaction_targets();
68
69 public:
70 G1FullGCPrepareTask(G1FullCollector* collector);
71 void work(uint worker_id);
72 // After the Prepare phase, are there any unused (empty) regions (compaction
73 // targets) at the end of any compaction queues?
74 bool has_free_compaction_targets();
75
76 private:
77 class G1CalculatePointersClosure : public HeapRegionClosure {
78 G1CollectedHeap* _g1h;
79 G1FullCollector* _collector;
80 G1CMBitMap* _bitmap;
81 G1FullGCCompactionPoint* _cp;
82
83 void prepare_for_compaction(HeapRegion* hr);
84
85 public:
86 G1CalculatePointersClosure(G1FullCollector* collector,
87 G1FullGCCompactionPoint* cp);
88
89 bool do_heap_region(HeapRegion* hr);
90 };
91
92 template <bool ALT_FWD>
93 class G1PrepareCompactLiveClosure : public StackObj {
94 G1FullGCCompactionPoint* _cp;
95
96 public:
97 G1PrepareCompactLiveClosure(G1FullGCCompactionPoint* cp);
98 size_t apply(oop object);
99 };
100 };
101
102 // Closure to re-prepare objects in the serial compaction point queue regions for
103 // serial compaction.
104 template <bool ALT_FWD>
105 class G1SerialRePrepareClosure : public StackObj {
106 G1FullGCCompactionPoint* _cp;
107 HeapWord* _dense_prefix_top;
108
109 public:
110 G1SerialRePrepareClosure(G1FullGCCompactionPoint* hrcp, HeapWord* dense_prefix_top) :
111 _cp(hrcp),
112 _dense_prefix_top(dense_prefix_top) { }
113
114 inline size_t apply(oop obj);
115 };
116
117 #endif // SHARE_GC_G1_G1FULLGCPREPARETASK_HPP